The technical basis of the digital earth, what is the digital earth

The digital earth is the digital reproduction and re-recognition of the unity of the real earth and its related phenomena, and is the comprehensive application of various technologies such as remote sensing technology, global positioning system, geographic information system, virtual technology, and network technology. Organize the relevant information and data of each definite point on the earth (the range of the point can be large or small according to the need), and then further combine all such points on the earth to construct a virtual earth that can contain most of the data and information of nature and human beings, which is the digital earth.

The core idea of Digital Earth is twofold:

The first is to use digital means to deal with the problems of the earth in a unified manner;

Digital limb technique refers to the use of two numbers, 0 and 1Processing, Storage, and Transmission of Informationtechnology.

There are two foundations of contemporary electronic information technology: (1) microelectronics and optical fiber technology and (2) digital technology.

Digital technology is the trend of the development of electronic information technology.

Bits can be 0 or 1, which are not quantitative concepts, but represent two different states. Therefore, the operation of the bit requires the use of logical operations. The basic rules of logical operation of bits:

When transmitting binary information in a computer network, the unit of measurement for the transmission rate is different from the above because it is a one-bit serial transmission, and the decimal system is used. The most commonly used units of rate are: bits of seconds (bs) or bps

The earth is so big for humans that we tend to focus on the local areas under our feet. How can we fully and quickly understand the earth we live on? With the rapid development of information technology, we can now create a digital earth.

The so-called digital earth is based on computer technology, multi-technology and large-scale storage technology, with broadband network as a link, using massive earth information to carry out multi-resolution, multi-scale, multi-time and space-time and multi-type three-dimensional description of the earth, and use it as a tool to support and improve human activities and quality of life.

The core of the Digital Earth is geospatial information science, and the Global Positioning System (GPS), Geographic Information System (GIS) and Remote Sensing Technology (RS) are the three most important technical foundations. Eighty per cent of the information that human beings are exposed to is related to geographical location and spatial distribution, and geospatial information is the goods and vehicles on the information superhighway. The Digital Earth includes not only high-resolution satellite images of the Earth, but also digital maps, as well as economic, social, and demographic information, and its applications are largely beyond our imagination.

The digital earth is making its way into thousands of households and industries.

Digital Earth and Precision Agriculture.

Digital Earth and Intelligent Transportation.

The intelligent transportation system is based on the digital earth and establishes a real-time, accurate and efficient integrated transportation and management system that plays a role in a wide range and in all directions, so as to realize the intelligent operation function of the means of transportation on the road. Specifically, the system collects various road traffic and service information after centralized processing by the traffic management center, and transmits to each user of the road transport system (driver, resident, police station, parking lot, transportation company, hospital, ambulance and obstacle removal department), and travelers can select traffic mode and traffic route in real time; The traffic management department can automatically carry out reasonable traffic diversion, control and accident handling; The transportation department can grasp the transportation status of the vehicle at any time and make reasonable scheduling. Thus, the traffic flow on the road network is in the best condition, traffic congestion and congestion are improved, the traffic capacity of the road network is maximized, and the mobility, safety and productivity of the entire road transport system are improved.

In this way, it also enables the public to use road transport facilities and energy efficiently.

In conclusion, with the development of related technologies, the digital earth will have a huge impact on all aspects of social life. Some of these effects we can imagine, and some of them may not be possible for us today.

on the Internet.

The concept of digital earth was originally proposed by the former vice president of the United States, Al Gore, and its core content is the digitization of global information. Digital Earth mainly refers to the application of geographic information system, remote sensing, global positioning system and other technologies to digitally obtain, process and apply spatial data on the earth's natural and human factors, and solve various global problems on this basis. Nowadays, the information technology revolution has swept the world, which has brought earth-shaking changes to the technical means and concepts of human beings in processing and analyzing the earth's spatial data.

In this case, one can integrate the geographical coordinates to form a digital globe. With the help of this digital earth, people can understand any place and any aspect of the earth according to the coordinates of the earth. Digital Earth is a digital emphasis and recognition of the unity of the real earth and its related phenomena, with two core ideas:

The first is to use digital means to deal with the earth's problems in a unified manner; The second is to make maximum use of information resources. The digital earth is composed of the following systems: data acquisition and update system, data processing and storage system, information extraction and analysis system, data and information dissemination system, database system, network system, special software system, etc.

The digital earth can contain more than 80% of human information resources, and is the main core of future information resources.

Digital Earth is a concept closely related to GIS, the Internet, virtual reality and other high-tech concepts put forward by Vice President Gore of the United States in his speech entitled "Digital Earth: Understanding of the Human Planet in the New Century" delivered at the opening ceremony of the California Science Center in January 1998. In Gore's article, he sees the digital Earth as "a three-dimensional, multi-resolution representation of the Earth, capable of putting in a large amount of geographic data." In the following intuitive example explanation of the digital earth, it can be found that Gore's digital geoscience is the product of the combination of the whole earth, all-round GIS, virtual reality technology, and network technology.

Obviously, in the face of such a huge project, any organization, enterprise or academic institution cannot be completed independently, and it requires the joint efforts of thousands of individuals, companies, research institutions and organizations. The technical problems to be solved by Digital Earth include computer science, massive data storage, satellite remote sensing technology, interoperability, metadata, etc. It is foreseeable that with the development of geospatial informatics, the establishment of the digital earth will certainly promote the modernization of surveying and mapping, establish closer ties between surveying and mapping and the entire national economy, make greater contributions, and produce huge economic and social benefits in the future and in the knowledge-based economy society.

Digital earth refers to the establishment of an earth information model, which collects, sorts and summarizes information from every corner of the earth, and establishes a complete information model according to the geographical coordinates of the earth and connects it with the network, so that everyone on the earth can quickly, completely and vividly understand the macro and micro conditions of the earth, and give full play to the role of these data.

Since its birth, the earth has accumulated a large amount of information about its own life and related to it, which is an objectively existing material phenomenon. Therefore, living and non-living things on Earth are always shrouded in the vast information field of the Earth and memorize this information. However, living and non-living things on the earth have never expressed this information scientifically, systematically, naturally and objectively, resulting in all kinds of inherent misunderstandings and contradictions, which are not conducive to the sustainable survival and development of living and non-living things on the earth.

The higher intelligent beings on the earth -- human beings have discovered some laws of nature, society and thinking, and have thus made new achievements in space technology, electronic technology, communication technology, computer technology, biotechnology, management science and thinking science, and tried to use them to express and understand the world, so as to find more laws of nature, society and thinking, solve the various contradictions between nature, human society and human thinking itself and each other, and promote the progress of human civilization.

The digital earth is the earth's information field reproduced by human beings in the form of numbers, and it is an information-based earth. It includes the acquisition, processing, transmission, storage management, retrieval, decision analysis and expression of earth information. It is externally manifested as a super-large parallel, interconnected and intelligent computer management information system.

Various sensors in space, underground and on the ground, computer networks, computer data processing centers, and biological and non-living information front-ends, terminals and carriers are the infrastructure of the digital earth.

From the perspective of geoscience technology in a narrow sense, digital earth technology mainly includes geographic information system (GIS), remote sensing (RS) and global positioning system (GPS) and other technologies. American Vice President Gore believes that the digital earth refers to the virtual earth based on the earth's coordinates, with multi-resolution, composed of massive data, and can be expressed in three dimensions.

The future of the Digital Earth is the Digital Universe. It indicates that there is more room for development and a longer development time for human beings on earth.

Digital Earth: The Digital Earth.

What is the concept and function of the digital earth?

Age: 4.6 billion years.

Revolution period: about 365 days.

Return Year Length:

Sky. Orbit: elliptical in shape. The aphelion point is at the beginning of July.

The perihelion is at the beginning of January.

Rotation period: sidereal days: about 23Hours, 56 minutes, 4 seconds. Solar day: 24 hours.

Rotation direction: from west to east.

Yellow and red corners. The angle at which the ecliptic plane meets the equatorial plane.

Polar radius: The distance from the center of the earth to the north or south pole, about 3950 miles (

km) (the difference between the poles is negligible).

Equatorial radius: The distance from the center of the earth to the equator, about 3963 miles (

km). Average radius: Approximately 3959 miles (

km) is the average of the distance from the center of the earth to all points on the earth's surface.

Volume: 1,083.2 billion cubic kilometers.

Mass: tons. Average density such as piper:

g/cm^3

The earth's surface is only a slag.

100 million square kilometers.

Ocean area: 100 million square kilometers.

Atmosphere: Main components: nitrogen (and oxygen) (.

Earth's crust: main components: oxygen (47%), silicon (28%) and aluminium (8%).

Surface atmospheric pressure:

Millibar. Satellites (natural): 1 (Moon.

Floor area: ra=6378137

This paragraph] the mass of the earth.

Cavendish Sh. It is believed that the mass of the Earth is about 6 10 24 kg.

The equatorial radius of the earth ra=6378137m, the polar radius rb=6356752m, the flattening rate e=1, ignoring the non-spherical symmetry of the earth, the average half-grip diameter r=. Gravitational acceleration at sea level at the equator.

The value of GA=, the value of gravitational acceleration at a certain sea level in the Arctic gb=, the universal standard value of gravitational acceleration g=, the rotation of the Earth.

The period is 23 hours, 56 minutes and 4 seconds (sidereal days), i.e. t=.

If the mass of the Earth is considered homogeneous, and the influence of other celestial bodies is ignored, the mass of the Earth can be calculated in the following way.

Method. 1. At the equator, the gravitational force of the Earth on an object of mass m is equal to the gravitational force of the object and the centripetal force that rotates with the Earth.

The sum is the method.

2. In the North Pole, without taking into account the rotation of the Earth, it is calculated as:

Method. 3. Treat the earth as a sphere with uniform mass, ignore the influence of rotation, take the average of the radius, and take the standard value of gravitational acceleration. then is.

The distance between the Moon and the Earth is r, and the lunar orbit period is 27 days, 7 hours, 43 minutes and 11 seconds (sidereal days), that is, the moon and the earth are regarded as mass points, and the mass of the moon is m months.

Method. Fourth, for.

The Earth's annual age is 4.6 billion years, its volume is 1,083.2 billion cubic kilometers, and its mass is 60,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 29% of the planet is land and 71% is ocean. The Earth was formed 4.6 billion years ago, and about 1.6 billion years ago, the Earth only attacked and dismantled for 9 hours day and night, which is much faster than the current rotation, about 800 days a day.

The age of the Earth is 4.6 billion years, the volume is 1,083.2 billion cubic kilometers, and the mass is 60,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 29% of the planet is land and 71% is ocean. The Earth was formed 4.6 billion years ago, about 1.6 billion years ago, when the Earth had only 9 hours of day and night, which was much faster than it is now, with more than 800 days per day.

The knowledge framework and exercises of the digital collapse of the earth lead and circle talk about the hidden praise.